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1.
Previous research has shown that caffeine and a<15-min nap effectively and separately reduce sleepiness in drivers for I hr. In the present study, we examined in 12 sleepy individuals the treatments combined, taken during a 30-min break, prior to a longer (2 hr) continuous monotonous afternoon drive in a car simulator. Nonnap comparisons were 200 mg caffeine only and placebo. For placebo, driving incidents. Subjective and electroencephalographic measures of sleepiness all reflected a mid-afternoon peak'. This peak was significantly reduced by caffeine and eliminated by the combined treatment, which reduced incidents to 9% of placebo levels versus 34% of placebo levels for caffeine alone. Naps comprising “nonsleep dozing” were still effective.  相似文献   
2.
Reduced activity of the red-cell sodium-potassium pump in human obesity   总被引:10,自引:0,他引:10  
Looking for evidence of reduced energy use in the cells of obese persons, we measured the numbers of sodium-potassium-pump units in erythrocytes from a group of 21 obese human subjects and found them to be reduced by 22 per cent as compared with those of nonobese controls (P <0.001). The cation-transport activity of the pump, as measured by 86rubidium uptake by the cells, we also reduced in parallel with decrease in pump units. An increased concentration of sodium in the red cells of obese subjectes was also found (9.6 +/- 0.7 vs. 7.1 +/- 0.6 mmol per liter of cells; P<0.01). This finding demonstrates independently the physiologic importance of reduced numbers of sodium-pump units and reduced pump activity as measured by ouabain binding and rubidium transport, respectively. The magnitude of the reduction in the number of pump units was found to be negatively correlated with the percentage of ideal body weight (r = 0.56, P<0.001); this observation suggests a possible role of abnormalities of the sodium pump in the pathophysiology of obesity.  相似文献   
3.
BACKGROUND: Although acute cholecystitis is one of the most common indications for abdominal surgery in patients with acquired immunodeficiency syndrome (AIDS), previous studies have reported disappointingly high morbidity and mortality among those patients who have undergone cholecystectomy. The aims of this study were to analyze the indications for and the outcome of cholecystectomy performed for acute cholecystitis in patients with AIDS. METHODS: We retrospectively reviewed the hospital charts of 53 patients with AIDS who underwent open or laparoscopic cholecystectomy from 1992 to 1997. Statistical analysis using the chi-square, Student's t, and Fisher exact tests was conducted to determine whether cause of cholecystitis, type of surgical approach, and CD4+ T-lymphocyte count influenced outcome. RESULTS: The clinical findings and imaging by ultrasonography were always reliable in establishing diagnosis and guiding treatment of acute cholecystitis. Open cholecystectomy was performed in 24 patients (45%). The procedure was begun laparoscopically in 29 patients (55%) and converted to open in 4 (14%). The pathologic findings showed acalculous cholecystitis in 19 patients (36%) and cholelithiasis in 32 (60%). Morbidity was 34% and mortality was 2%. Type of operative approach, cause of cholecystitis, and CD4+ T-lymphocyte count (greater or less than 50 cells/mm3) did not significantly affect morbidity and mortality. The length of hospital stay was significantly influenced by the CD4+ T-lymphocyte count. CONCLUSIONS: These findings suggest that in most patients with AIDS, laparoscopic or open cholecystectomy may be performed with significant but acceptable morbidity and low mortality.  相似文献   
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5.
The aim of the authors was to investigate whether living as a minority has an influence on the dental fear and anxiety values. In this study 201 volunteers (n = 201, inside border Hungarians 144, outside border Hungarians 57, male 90, female 111; age 8 to 83 years, mean 44 +/- 16 yrs.) were investigated. Our methods included collection of demographic data (gender, age, marital status, profession), and administration of the Hungarian versions of dental fear and anxiety related scales namely: DAS, DAQ, DASQ, DFS, DBS, STAI-S, STAI-T and Expectation Scale. Mean values of the scales were: DAS: 10,34 +/- 3,54; DAQ: 2,3 +/- 1,15; DASQ: 12,58 +/- 4,55; DFS: 40,37 +/- 15,67; DBS: 32,89 +/- 12,94; Expectation Scale: 2,87 +/- 3,56, STAI-S: 39,51 +/- 10,68; STAI-T 41,65 +/- 9,08. The mean scores of all the scales were higher in the case of Hungarians living inside the borders of Hungary. The differences were significant in the case of DAS, DAQ, DASQ and DFS scales (p < 0,05). Data of our study indicate that living as a minority not necessarily leads to the increase of dental fear and anxiety.  相似文献   
6.
M A De Luise  M Harker 《Diabetes》1988,37(1):33-37
Clonal osteoblast-like cells derived from a rat osteogenic sarcoma (UMR 106-06) were shown to possess specific, high-affinity binding sites for insulin, with a receptor density of 22,000/cell. The hormone, at physiologic concentrations (1-10 ng/ml), was found to stimulate active K+ transport into these cells, the effect being mediated via the Na+-K+ pump. Alterations in insulin-receptor status by treatment of cells with glucocorticoids or exposure to subphysiologic pH was reflected in parallel changes in the sensitivity of the K+-uptake process to the hormone. We conclude that insulin can directly affect the metabolism of bone cells and that the hormone's action on transmembrane ion transport may be linked to interaction with its cell surface receptors.  相似文献   
7.
Cutaneous leishmaniasis represents a public health problem that affects 85 countries. It is an endemic disease in Brazil, having an important socioeconomic impact. An exuberant case of cutaneous leishmaniasis is reported herein. A 28-year-old male patient with Down syndrome had had verrucous plaques on the back for over a year, with progressive growth. PCR of a lesion sample was positive for Leishmania braziliensis. The patient's condition was classified as atypical cutaneous leishmaniasis. He was successfully treated with amphotericin B and miltefosine. The treatment remains a challenge, given the toxicity and low cure rate of the currently recommended drugs.  相似文献   
8.

Purpose of Review

Left ventricular assist device (LVAD) therapy serves as mainstay therapy for bridge to transplantation and destination therapy. Evidence is now mounting on the role of LVAD therapy as bridge to recovery. In the current review, we will summarize the data on biomarkers of myocardial recovery following LVAD implantation.

Recent Findings

Myocardial recovery can occur spontaneously, following pharmacological intervention and in the setting of mechanical circulatory support such as LVAD. Several biomarkers such as B-type natriuretic peptide (BNP), N-terminal pro B-type natriuretic peptide (NT-proBNP), ST2, etc. have been identified and are being used to guide medical therapy in heart failure (HF) patients. However, recent data raised concern that those biomarkers may not be helpful in managing heart failure patients in general, and as such questioned their use in the advanced heart failure population. At this point, the use of biomarker to identify patients with myocardial recovery during LVAD support has not been established, and LVAD explantation remains a decision driven by echocardiographic and hemodynamics improvement.

Summary

HF biomarkers in monitoring myocardial and neurohormonal activation response to mechanical unloading and medical therapy could be valuable. However, at this time, there is inadequate evidence to select a single or a set of HF biomarkers to reliably identify patients bridged to recovery for LVAD explantation.
  相似文献   
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10.
Thrombotic microangiopathy (TMA) is a life-threatening condition that affects some, but not all, recipients of vascular endothelial growth factor (VEGF) inhibitors given as part of chemotherapy. TMA is also a complication of preeclampsia, a disease characterized by excess production of the VEGF-scavenging soluble VEGF receptor 1 (soluble fms-like tyrosine kinase 1; sFlt-1). Risk factors for VEGF inhibitor–related TMA remain unknown. We hypothesized that deficiency of the VWF-cleaving ADAMTS13 endopeptidase contributes to the development of VEGF inhibitor–related TMA. ADAMTS13−/− mice overexpressing sFlt-1 presented all hallmarks of TMA, including thrombocytopenia, schistocytosis, anemia, and VWF-positive microthrombi in multiple organs. Similar to VEGF inhibitor–related TMA in humans, these mice exhibited severely impaired kidney function and hypertension. In contrast, wild-type mice overexpressing sFlt-1 developed modest hypertension but no other features of TMA. Recombinant ADAMTS13 therapy ameliorated all symptoms of TMA in ADAMTS13−/− mice overexpressing sFlt-1 and normalized BP in wild-type mice. ADAMTS13 activity may thus be a critical determinant for the development of TMA secondary to VEGF inhibition. Administration of recombinant ADAMTS13 may serve as a therapeutic approach to treat or prevent thrombotic complications of VEGF inhibition.  相似文献   
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